Method of producing and maintaining a high vacuum.



F. M. MEYER. METHOD OF PRODUCING AND MAINTAINING A HIGH VACUUM. APPLICATION FILED DEC. 16, 1913.

1,1 00,694, Patented June 16,1914.

W/TNEss n; 1 A //YVENT"07? tion with a vacuum pump; and a pipe 30 and which outlet is siding at Osnabriick, in Hanover, German ful Improvements in Methods of Producing the following is a specification.

I plate f UNITED STATES PATENT orrioia.

FRANS M. MEYER, OF OSNABRTTGK, GERMANY, ASSIGNOR TO THE FIRM 0F SUDFELDI & 00., OF MELLE, HANOVER, GEEMANY.

Specification of Letters Patent.

Pa tented June 16, 191.4.

Application filed December 18, 1913'. Serial No. 807,146.

To all whom. it may concern: c

, Be it known that I, FRANS M. MEYEIQTG Empire, have invented certain new and useand Maintaining High Vacuums, of which This invention relates to a method of producing and maintaining a very high 'vacuum, especiallyada 'ited for'use in distillation processes.

The accompanying drawing represents a vertical section of one form of apparatus adapted for carrying out this method. V

This apparatus comprises a cylinder 10 adapted for connection with a still or other source of .fluid containing vapor to be con densed, a cylinder 20 adapted for connecejector 40 connecting said cylinders.

' The cylinder 10 is provided with interior plates 11 and 12 which with the outer shell form an intermediate cooling chamber 13. An admission chamber 14 is located atthe top of the cylinder and a chamber or incloscd space i is located in the lower part thereof. Tubes 15 pass through the intermediate cooling chamber 13'and at their up per ends open into the admission chamber 14 and at their lower ends into the incloscd chamber or space The top of the admission chamber 14 1s connected by a pipe a with a still not shown. The cooling cham her #13 has at its bottom an inlet pipe 6 for the inflow of cooling water and near its top an. outlet 0 for the outflow ofsaid liquid. The chamber f is provided near its top with an outlet-f for the passage ,of the gases, guarded. by an inclined The cylinder 20 has an inlet opening 21 in its top and an outlet opening e near its top. Vertical plates 22 and 23 are disposed in the upper part of said cylinder and a horizontal ba'iile plate 24 is disposed below said vertical plates.

The ejector 40 is mounted on the top of the cylinder 20 opposite the opening 21 thereof. This cjectormay be of any ordinary or suitable construction. As shown it i provided at its up er end with a nipple d which is adapted or connection with a source of air or equivalent noncondcnsing gas which cools under expansion and which j 1s preicrably supplied under a high presi haust through the pipe 6 or other point of i connection with the air'purnp andthe ejector =10 between said inclosed spaces is in inductive connection with the primary s ace so as to draw the gas therefrom and tiirce it into the secondary space'.

In carrying out this process by the use of the apparatus described the cylinder 10 containing the primary inclosed. space f is connected with a still or other source of supply, the secondary chamber or inclosed space 20 is connected with a vacuum pump and the ejector 40. in inductive connection withsa'id primary space is adapted to admit preferably under pressure dry air oran equivalent noncondensablc gas,.which cools on expansion. The fluid, containing vapor to be condensed, such for instance as a distillate, is passed through-the pipe a into the admission chamber 14 of the cylinder 10, thence through the tubes 15 which pass through the cooling chamber 13 into the pri-' mary chamber or inclosed space f. The tubes are surrounded by cooling water flowing into the cooling chamber through the inlet 6 and out therefrom through the outlet (3. In passing through these pipes the fluid is subjected to a condensing operation, and more or less heat is extracted by conduction through the" walls of the tube and more or less of the vapor contained in the fluid is condensed on the inner walls of the tubes and dropped into the primary condensate chamber or inclosed space 7. The fluid containing some remaining vapor to be condensed is drawn from the primary inclosed a space f through the connecting pipe 30 and the ejector 40 under the double suction of the air pump and said ejector, and discharged into the secondary chamber or inclosed space 20. The air or equivalent noncondensable gas entering through the ejector 40 at a higher pressure than the pressure of the gas within the secondary chamber 20 commingles with the fluid therein and under its natural expansion has a cooling effect on said fluid and operates to condense whatever vapors are drawn into said chamber 20; the vapors so condensed collectlng 1n the lower part of said chamber.

In consequence of the low resistance of the secondary chamber 20 to the jet of comiressed air or other suitable compressed or liquefied gas, the latter enters said chamber or'spacc at a very high velocity and the fluid is sucked'from the primary chamber f to be evacuated, and a higher vacuum is obtained than could be obtained if a pump alone Were used.

It has been found that With a vacuum air under the influence of the vacuum in the chamber or inclosed space 20 the air is considerably cooled, whereby any "apors remaining in the gases are condensed and collected at the bottom of the chamber 20 so that no product of the distillation is lost.

I claim as my invention:

The process which consists in subjecting connected primary and secondary inclcs'ed spaces to a suction exhaust from a point of said secondary space and injecting into said secondary space at a point of inductive connection \vitlrsaid primary space, a jet of noncondensable gas.

In testimony whereof I affix my signature in presence of two witnesses.

FRANS M. MEYER. 

